There are a variety of fish that are monitored around Koh Tao as indicators of good biodiversity.
Sweetlips and Snappers
Sweetlips and Snappers are an important commercial fish in local, regional, and global markets.
Although Surgeonfish population sizes are low in Koh Tao, there presence and abundance is monitored as indicators of bidodiversity.
Rabbitfish are important in the ecosystem because they are prey to various organisms on the reef, helping to keep there population numbers under control. They are also a good indication of reef health.
Butterflyfish feed on coral polyps, thus they indicate coral abundance and overall coral health.
Triggerfish are one of the most successful invertabrate predators on the reef but their population is sensitive to environmental changes making them a good indicator species for Koh Tao.
Some rays speialise on eating benthic invertabrates while others filter feed plankton from the water. These two feeding strategies address different environments which are both sensitive to natural and anthropogenic stresses making rays a good indicator species.
Groupers, like Triggerfish are great predators on the reef but their population is sensitive to fishing and habitat destruction making them a good indicator species for Koh Tao.
Parrotfish feed on periphyton and other algae attached to substrate such as hard coral. This can cause erosion of hard coral in areas where popuations are high. This is on reason their numbers are closely monitored around Koh Tao.
Turtles are extremly sensitive to new resort developments near beaches as they nest on shore on the beaches and they always nest on the same beach each year. Therefore population numbers are a key indication in Koh Tao of how the continuing development and increase of visitors is affecting the reef.